feat(coreos-base/oem-gce): support cloudconfig

With this pull request we can support a cloudconfig sent to the
user-data metadata key. Tested etcd and fleet bootstrapping and ssh key
insertion.

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-gce/files/cloud-config.yml

@@ -2,7 +2,27 @@
 
 coreos:
     units:
-      - name: ec2-ssh-key.service
+      - name: gce-coreos-cloudinit.service
+        runtime: yes
+        content: |
+          [Unit]
+          Requires=gce-setup-environment.service
+          After=gce-setup-environment.service
+
+          [Service]
+          EnvironmentFile=/etc/environment
+          ExecStart=/usr/share/oem/bin/gce-coreos-cloudinit
+      - name: gce-setup-environment.service
+        runtime: yes
+        content: |
+          [Unit]
+          Description=Setup environment variables from metadata
+
+          [Service]
+          Type=oneshot
+          StandardOutput=journal+console
+          ExecStart=/usr/share/oem/bin/gce-setup-environment /etc/environment
+      - name: gce-ssh-key.service
         runtime: yes
         content: |
           [Unit]

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-gce/files/gce-coreos-cloudinit

@@ -0,0 +1,10 @@
+#!/bin/bash -e
+
+TMPFILE=$(mktemp /tmp/XXXXXX-cloud-init)
+trap 'echo "removing ${TMPFILE}"; rm -f ${TMPFILE}' INT TERM EXIT
+
+curl --retry 5 --retry-delay 2 --silent --fail \
+		"http://169.254.169.254/computeMetadata/v1/instance/attributes/user-data" \
+                -H "X-Google-Metadata-Request: True" > ${TMPFILE}
+
+/usr/bin/coreos-cloudinit --from-file=${TMPFILE}

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-gce/files/gce-setup-environment

@@ -0,0 +1,31 @@
+#!/bin/bash +x
+
+ENV=$1
+
+if [ -z "$ENV" ]; then
+        echo usage: $0 /etc/environment
+        exit 1
+fi
+
+# test for rw
+touch $ENV
+if [ $? -ne 0 ]; then
+        echo exiting, unable to modify: $ENV
+        exit 1
+fi
+
+sed -i -e '/^COREOS_PUBLIC_IPV4=/d' \
+    -e '/^COREOS_PRIVATE_IPV4=/d' \
+    "${ENV}"
+
+external_ip=$(curl --retry 5 --retry-delay 2 --silent --fail \
+		"http://169.254.169.254/computeMetadata/v1/instance/network-interfaces/0/access-configs/0/external-ip" \
+		-H "X-Google-Metadata-Request: True")
+
+
+public_ip=$(curl --retry 5 --retry-delay 2 --silent --fail \
+		"http://169.254.169.254/computeMetadata/v1/instance/network-interfaces/0/ip" \
+		-H "X-Google-Metadata-Request: True")
+
+echo COREOS_PUBLIC_IPV4=${external_ip} >> $ENV
+echo COREOS_PRIVATE_IPV4=${public_ip} >> $ENV

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-gce/files/gce-ssh-key

@@ -2,7 +2,7 @@
 
 set -e
 
-URL_PREFIX="http://metadata/computeMetadata/v1beta1/"
+URL_PREFIX="http://169.254.169.254/computeMetadata/v1beta1/"
 
 update_keys() {
     local id="$1"

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-gce/oem-gce-0.0.1.ebuild

@@ -19,6 +19,12 @@ src_install() {
 	into "/"
 	dobin ${FILESDIR}/gce-ssh-key
 
+	into "/"
+	dobin ${FILESDIR}/gce-coreos-cloudinit
+
+	into "/"
+	dobin ${FILESDIR}/gce-setup-environment
+
 	insinto "/"
 	doins ${FILESDIR}/cloud-config.yml
 }